Currently, the clinical diagnosis of Alzheimer's disease (AD) and/or mild cognitive impairment (MCI) generally requires an evaluation of medical history and physical examination including neurological, neuropsychological, and psychiatric assessment, as well as various biological, radiological and electrophysiological tests, such as for instance measuring brain volume or activity measurements derived from neuroimaging modalities such as magnetic resonance imaging (MRI) or positron emission tomography (PET) of relevant brain regions. However, neuroimaging modalities are expensive, labor-intensive and not universally available. Despite the battery of tests available, a definitive diagnosis of AD can only be achieved by post-mortem brain examination. Thus there is a need for additional test and methods of assessing dementia and other cognitive disorders.